Is your project folder structure as per tutorial? If so please put your ZIP file and attach to next reply I will try to have look at it (you need to click "Use Advanced Editor" and bellow text editing area will be Manage Attachment options to attach ZIP of the project)
Also please let me know what IDE you use.

Error:
Multiple annotations found at this line:
- Attribute "xmlns:xsi" must be declared for element type "web-app".
- Attribute "version" must be declared for element type "web-app".
- Attribute "xsi:schemaLocation" must be declared for element type
"web-app".

Given that you did project development in IDE instead of command line build as I did in original tutorial project folder structure is slightly different. Mainly the contenten of "classes" folder is moved to 'src" (you can see in attached file).

However as hard as I tried I couldn't get rid of error about <jsp:useBean id="students" type="ArrayList<beans.UserBean>" scope="session" /> . Page imports are fine, UsrBean is found I guess since there is no error on the line above this that retrieve userBean object from session.

Can some Eclipse user have look and check attached project folder to see if he/she will be wiser why Eclipse is moaning so much?

PS: Cascading style sheets and image is missing from there, but that is not important at the moment.